Intertidal Community Health

Importance / Issues

Rocky intertidal zones provide habitat and food for marine and terrestrial organisms and these communities, in turn, provide important economic, scientific, educational, and recreational value for humans.  Intertidal habitats in New England represent some of the best studied ecological communities, in part because the dominant species are large and grow rapidly, and the strong zonation across small spatial scales is attractive for field manipulations (Connell 1961, Paine 1966, Lubchenco 1978).  It is widely recognized that these communities are shaped both by natural abiotic (e.g. dessication) and biotic factors (e.g. competition and predation).  However, these communities are also affected by a variety of anthropogenic stressors including climate change, invasive species, pollution, and trampling.  While the ecological consequences of some of these stressors (e.g. some invasive species) are known for short-term, within-year experiments, their effects are largely unknown over longer time periods.

Protocol Development & Status

The protocol is in development and will be piloted in 2008.  Acadia NP will have 5-7 pilot plots installed and Boston Harbor Islands will have 7 pilot plots installed. The number of plots for long-term monitoring in both parks will be established as part of the pilot project. This protocol is based on the initial Rocky Intertidal Protocol Development Summary.

Potential Measures

The Rocky Intertidal Monitoring Protocol has defined 20 target species or species groups to monitor and will correlate changes in species abundance with changes in environmental stress.

Preliminary Monitoring Objective

A preliminary objective of this protocol is to monitor changes in densities of target species in fixed plots over time (both seasonal and annual).  Because intertidal species in Acadia NP and Boston Harbor Islands are patchy or heterogeneous over small spatial scales (pers. obs.) and because logistics will limit the number of samples that can be taken at any given site, fixed plots will be monitored rather than random points. 

Contact Information

Principle Investigators: Jeremy D. Long

Email: Jeremy D. Long

Geoffrey C. Trussell

Email: Geoffrey C. Trussell

References

Connell, J.H. (1961).  The influence of interspecific competition and other factors on the distribution of the barnacle Chthamalus stellatus. Ecology 42: 710-723.

Lubchenco, J. (1978).  Plant species diversity in a marine intertidal community: importance of herbivore food preference and algal competitive abilities.  American Naturalist 112: 23-39.

Paine, R.T. (1966).  Food web complexity and species diversity.  American Naturalist 100: 65-75.